When your dog rolls in the grass after you bathe them you may want to scold them, but there is a perfect reason for this behaviour.
Dog noses have over 220 million olfactory receptors compared to our 5 million.
Dogs don't like certain fragrances, especially those containing alcohol, which we find pleasant. Instead, they prefer odours that we absolutely hate (rotten smells, faeces...). By rolling in the grass, they are not trying to get dirty or spite you, but just attempting to get rid of that bad smell and cover themselves in an odour that they like better.
Probably, one of the reasons for this behaviour is the fact that dogs descend from wolves, and when a wolf smells the presence of another animal, they roll in it to get the same smell. By doing this, when they return to the pack they transmit the smell to the other wolves that come to greet them. It's a way of communicating.
So, don't worry if your dog likes rolling in the grass, but be careful if the lawn has been treated with pesticides or other harmful substances. Also, keep in mind that there may be ticks and fleas in the grass, so make sure your pet is well protected and use anti flea and tick products. For example, we suggest one of our products Insect Repellent Neem Oil Mist an excellent integration to traditional repellents.